Just got 2 ADFs from a LPS, I've never had any before. I need to know what to use to condition their water, I have Biotize conditioner that I used for my snapping turtle when I had one and NovAqua for the bettas. It says that the NovAqua adds protective skin slime, which I'm not sure is good for the frogs. Also is it okay to put a little aquarium salt in with them while I quarantine them like I would with bettas? Also what should I look out for in terms of sicknesses? And is it safe for me to use Methylene in their water?

Yay, a new frog owner!
Hmm, I would not bother with meth. blue or salt or anything else. Frogs are very different than fish and it won't be good for them.
That said, the conditioner you use for your fish is fine for them.
Sickness.. the most common thing is chytrid fungus, if that occurs you won't be able to do anything about it, sadly. If your frogs make it past the 3 month mark alive, then you shouldn't worry about chytrid for them.. that said if you want to add to the frog colony, all new frogs must be quarantined for 3 months.

Thanks for the info. Could you also tell me how much and how often to feed them. And I was told to feed them frog and tadpole bites, is there anything else I could feed them? I've got a bunch of really tiny baby mealworms, could I feed them those too? Is there anything that I can use in their water as a disease/parasite/fungus preventative (I want to put them in with my bettas after the quarantine, but first I want to make sure that they pose no health threat to them)?

No, they will not pass anything over to your fish. I have no idea on medicating frogs, Gizmothefreaky does and she has tons of experience with them, she also has an ADF thread in the compatibility section (this section..) you should go over.
If your frogs are babies they should be fed every day.. bigger adults are fine every other day.
Mine take pellets, some don't. Bloodworms are fine, as well as brine shrimp and any other frozen goodies. Not sure on meal worms, but I think Gizmo would know.. Also frozen tilapia filets cut into tiny pieces are popular.